Ash removal apparatus



Aug- 3, 1954 c. K. BIRCH ASH` REMOVAL APPARATUS Filed Maron 19, 1949INVENTOR. ham/es /f z'rc M uw MMV/3mm ATTORNEYS Patented Aug. 3,` 1954ASH REMOVAL APPARATUS Charles K. Birch, Montclair, N. J., assignor toLehigh Valley Coal Sales Company, New York, N. Y., a corporation ofDelaware Application March 19, 1949, Serial No. 82,341

2 Claims. 1

This invention is directed to the provision of improved ash removalapparatus for transferring ashes from a coal-fired furnace to an ashrecep-\ tacle located at a distance from the furnace. The new apparatusmakes use of a suction system for effecting transfer of the ashes from ahopper beneath the furnace to the ash receptacle. Suction systems forash removal have been proposed heretofore, but have not been generallyaccepted for use in connection with small furnaces such as householdheating furnaces. A careful study of the capabilities and limitations ofsuction systems has led me to the conclusion that such systems are inprinciple sound for eliminating the hard and dirty job of removing ashesby hand from a coal-red furnace; but for the system to be practicallyuseful special provisions must be made to prevent clogging, and thesystem must be essentially automatic in its operation in order for it tobe suitable for widespread use, and especially-for use with furnaces forhousehold heating and with other furnaces operated by mechanicallyuntrained persons. Lack of effective provisions to accomplish these endshave been responsible for the indifferent success of the suction systemsfor ash removal heretofore proposed.

The ash removal system of the invention is particularly designed tominimize any opportunity for clogging, to be quiet and clean in itsoperation, to be essentially automatic, and to be constructed at a costmaking it attractive for use in conjunction with household heating'furnaces and other small coal-fired furnace installations. tioncomprises a coal-fired furnace having an ash crushing grate providedwith the usual grate shaking lever, which in turn is equipped with aremovable shaking lever handle. An ash hopper is mounted vbeneath thegrate to receive ashes shaken therethrough. A suction box is connectedto the bottom of the hopper, and the hopper serves to direct the ashesinto it. The suction box is connected by a suction pipe to an ashseparator detachably mounted on an ash receptacle located at a distancefrom the furnace and in which the ashes ultimately are collected. Asuction fan, preferably mounted directly on the ash separator, isarranged so that its inlet is connected therewith. Its outlet may beconnected to a discharge vent or flue, or may be connected to adust'filter, or may simply'open directly to the atmosphere. The fan isdriven by an electric motor which preferably is energized through aswitch mounted adjacent the grate The complete apparatus of the inven- Ashaking lever and connected in circuit with a motor and with a source ofelectric power. If such a switch is used, means for closing it aremounted on the grate shaking lever in position to be engaged andactuated by the removable handle whenever the latter is attached to thegrate shaking lever. Thereby whenever the handle is applied to theshaking lever, the fan motor is automatically energized and creates aflow of air from the ash hopper through the suction box and suction pipeto the ash separator. Shaking the grate crushes the ashes as Well ascausing them to fall into the hopper, whence they are carried in the airstream through the suction pipe to the ash separator. There the coarseashes separate from the air stream and settle into the receptacle. Thusthe system is automatically set in operation and the ashes aretransferred to the receptacle by the simple steps of placing the handleon the grate shaking lever and shaking it in the usual manner.

The design of the grate is of importance to the operation of the systemas a Whole, for it must be capable of crushing whatever ashes passthrough it, when it is shaken, to a size ne enough so as not to causeclogging of the suction system. Also of importance to the operation ofthe system as a whole is the design and construction of the suction boxat the bottom of the hopper. Even fine ashes tend to accumulate at thispoint and cause the suction pipe to become clogged; but I have foundthat by providing a suction box of proper design at the bottom of thehopper, to which the suction pipe is connected, clogging can bevirtually completely prevented. Furthermore, the provision of a suctionbox permits the suction pipe to extend laterally from it, rather thanvertically down from the hopper, and so greatly decreases the head roomrequired below the grate for installing the system. The arrangement ofthe suction fan and ash separator directly over the ash receptaclerenders operation of the system clean in the building within which thefurnace is located by making the entire system within such building, upto the ash receptacle itself, operate under a reduced pressure and soprevent the possibility that leaks in the system will result in ash dustbeing discharged into the building atmosphere. Also by this arrangementthe noise incident to operation of the fan is produced at a point whereit is not objectionable.

The foregoing and other features of the new apparatus are described morein detail below with reference to the accompanying drawings,

which show a preferred embodiment of the new apparatus and in which Fig.1 is a more or less diagrammatic View, partially in section, of an ashremoval system according to the invention; and

Fig. 2 is a plan view looking down on the ash hopper of the furnace ofFig. l.

The :ash .removal `apparatus of the invention is shown-in Fig. l in"combination with a coalred furnace I0. The furnace is provided with agrate I I on which the coal is burned. A grate shaking lever I2 iittedwith a removable handle I3 is provided for shaking the grate and therebycausing the ash to drop into ahopper IES mounted directly beneath thegrate. connected to the bottom of the hopper, fand -one end of a suctionpipe I6 is rin .turn `connected to the bottom of the suction box. Theother end of the suction pipe connects with "an fasli separator Il'detachably mounted on an ash receptacle IS. In most installationsfthefash :rerceptacle will :belocated-:at a distance fromzand ,fat .fa:higher level :than the :furnace 1:0. A 4fan :I9 fis xmounted over :the`Vash separator, with its inletconduit -26 connected with the `interior'of the separator. The routlet :conduit `2I irornthe :fan oisfcomiectedto f-a zdischarge vent Aor ue22,

: tormay-alternatively:benonnected'to a dust filter tbag, :or :even:beopen to the atmosphere. The :fan: is :driven-thy an'electric'motor23.

'When .the :fammotor ,23 is energized, ythe fan draws air from ,thehopper I4 through-thezsucrtiontbox 'I5 and suctiongpipe it into:andzthrough 'fthe :separator ;I;'I. Ash delivered through the grate YII:when the latter shakenfis collected :in the current :of air'xin the:fsuction 'ibox Aand `is transierred thereby to zthe separator, whereinalmost :all ,of fthe v:ashzseiftles :out Yand drops :into fthe:receptacle zIS. 'The small amount fof :iine :ash vparticles that .dognot :settle are l:carried :in the air stream through:theifanandpthroughgits @outlet fnonduit :2i to 'the :discharge 'vent':22. 'The :air escapesthrough .the f .pores of the iilter abag `to theatmosphere AItrissfiecessary:thattheashcentering'thehopper Y :|14 benely :enough divided so :as :not to clog :the fsuctionzbox :It orfthe:suction "pipe I6. .Accord- I'ingly, the .grate .I:I iis idesigned to:crush vzthe .ash :passing through it into :the fhopper. Anadxvantageous form :of sgratepisfshowncinr my-.copend- .ing :application:Serial No. 4185,001), .-riled Septem- :ber 15,11950.

The ash =hopper :I4 .is supporteddirectly :below the 'grate '.-ifIonbrackets '.30 .fastenedto the :furmace structure. rlhe ihopper isdeined :by asub- .fstantially plane -front .wall FBI, :a vsubstanti-allyplane .rear :wall 32 anid. substantially `plane :side 'walls 33,1'all1ofwhich awalls'` slope inwardly :and rdmvnwardly'tow-ard each other.`Thesuctionliox 55:5 .atpthe "bottom :of Jthe 'hopper :is `most advan-'tageously ormedby extendingtheffront wall RBI andiside '-.walls v33 fof.the ahopper :substantially in their :respective planes downwardly `:toYa ibottom apex Bdfbeneath the zbottomof the fhopper itself bottom .offthe hopper zis Adernarked .by the A'lower'edge' 3'5 of 'thezhopper'rear wall .32) The y:rearfwall 3.6 .of the .suction box (as bestshown :in Eig. `1) nis curved .concavely'toward the front 'wall .,i. fe.lits lower Aportion `near the `suction .xbox :apex lbcurvesupwardlyandfaway-from the :front wall, and its .upper portion curves .back againtoward the front wall and joins with fthe ,rear wall 32 `of the.hopperat its .lower edge 35. .Thus the rear .wallof the ,suction .boxapproaches .the .front 4wall thereof .more closely at its upper edgethan at its mid-portion, and the maximum distance between the front andrear walls of the suction box occurs substantially midway between thetop and bottom edges of such rear wall. The suction pipe I6 is connectedto the front wall of the suction box I5 near its bottom apex, andextends laterally therefrom at an acute angle thereto.

I have ifoundithat the-provision of 'a suction box I5 is of importanceto prevent clogging of :the suction system. If the suction box isomitted .and .thesuction pipe is connected directly to the bottom of thehopper (especially if it extends hlaterally therefrom), the ash thatcollects at the -.bottomfof thehopper tends to clog the entrance to-thesuctionpipe. It is my present belief that .whenasuctionbox as describedabove is provided, it has the effect of so directing the current of air:created by the suction fan as to avoid or minimize any regions of lowair velocity in which :ash :particles @tend lto settle out .and collectin a :pipe-,clogging mass. A.In :any event, .the 3pm- :vision :of thesuction fbox is 'of- 'distinct advantage, tboth 'for :its -eiect -in:preventing clogging zand :because it .enables the suction :pipe :tovextend laterally from beneath :the .-furnace, thereby minimizing thespace required lbeneath'thegrate :for freaking the installation.

The ash separator :H to -which :the-other --end roi the :suction pipe:I5 wis connectedLis 4simply a chamber, `preferably cylindrical,v.closed at the tcpandiopen at-the.bottom. A ange' Visprovided; aboutVits `lowergperipliergy for: engaging with the upper edge :of -the ashreceptacle 4:8. The :flange :may -be lined with gasket material to.'Iacilitatemakingaftight jointr with :the receptacle. The: ashseparator .may .be permanently mounted in position, andthefashreceptacle. may be carried en -.a vertically .imovableplatform.that Imay :be raisedto bring the upper edge of the :receptacle intoengagement with zthe .flange :t3 to :form a .substantiallypressure-.tight joint during f normal use of theapparatua :and that maybe lowered 'when :desired through the distance of several inchesnecessary to permit withdrawal of .the receptacle -when it is tiine :toempty it. fAlternatively the ash receptacle may besetnza `rigid foor.and fsome `'special provision may be :made fon-raising .and loweringYthe -ash separator, :or sthefseparator .may .merelymest ori-,thereceptacle, fto tbe .manually .raised andflowered.

The-fan-inlet conduit 20, which is open atits lower end, extends'axially into :the ash separator through 'its :closed 4top and projectspreferzably-to-a point near its open fbottom. Thesu'c- :tionulipe I6, onthe otherhand, is preferably connected :to the side of`the*ash:separato1.:near.its top. Theseparatortprovides.a substantialfenflargement `in the suction system, Vin whichzthe velocity :of the:air :current `created .fby `the fan fis:low'-and in whichash particlescarried `by the fourrent of air .are'consequently given an 'oppor-Atunity to Vsettle out and Afall-.into the ash receprltacle. Generallyit .is advantageous to connect l the l'suction pipe 'L6 'tangentially.rather -than radially fto the ash separator, :so that the fdirectionfof air ow through thesseparator ismore :or .less circular. Thisresults'in imparting fa centrifugal A'force :to the ash "particles and :thereby:promotes `their separation .'from the current of alr.

The ,fan :I9 is .of conventional construction. Whatever 'very :fine ash-does :not settle -ou-t `in .the separator VI Tl (and it :is quite smallimamount) is carried rby `the -,current of air v:th-rough 1.the .fan

and is discharged through the vent 22. In some cases the vent 22 may bedispensed with and the fan outlet may discharge directly to theatmosphere. In other cases where conditions require catching even thevery small amount of fine ash that does not settle in the separator, afilter bag may be attached to the fan outlet conduit 2|.

In a typical installation of the new apparatus in combination with ahousehold heating furnace, the furnace itself is located in the basementof the building, and the ash receptacle, the separator, and the fan arelocated some distance away at ground level, whence it is relatively easyto carry away the ash receptacle, when it is full, for the purpose ofdisposing of the ashes.

In order to minimize any opportunity for clogging of the system, it isimportant to tranfer the ashes to the receptacle substantially as soonas they are passed through the grate into the hopper, and to avoidhaving them collected and stored, even for but a short period of time,in any part of the system between the grate and the receptacle. Thisinvolves making provision to operate the fan whenever the grate isshaken. A convenient way to accomplish this result essentiallyautomatically is to actuate the motor 23 (which drives the fan) througha normally open switch which is closed (to set the fan in operation)when the removable handle i3 is placed on the grate shaking lever I2.

It is evident from the foregoing that the ash removal system of theinvention is of uncomplicated construction, is easy to install, and issubstantially automatic in its operation (i. e. it requires nomanipulative steps beyond those normally involved in shaking the grateof a coal-fired furnace). It has also been found in use to be effectivefor removing ordinary coal ashes from a furnace to a receptacle remotefrom and at a substantially higher elevation than the furnace itself;and it has proved to be reliable and dependable. It therefore provides apractical means for eliminating the most objectionable feature incidentto the operation of small coal-fired furnaces, namely, the removal byhand of the ashes.

I claim:

1. In ash removal apparatus of the character described, an ash hopper, asuction box connected to said hopper at the bottom thereof and havingside Walls and a front wall inclined downwardly to a bottom apex, an ashremoval suction pipe connected to and extending substantially laterallyfrom the front wall of said suction box at the bottom thereof and at anacute angle thereto, the suction box having a closed rear Wall the lowerportion of which extends to the bottom of the suction pipe and curvesaway from the front wall and the upper portion of which curves backagain toward the front wall, the maximum distance between the front walland rear wall being at a point below the top edge of said rear wall andabove the bottom apex of the suction box.

2. In ash removal apparatus of the character` described, an ash hopperhaving substantially plane front, side and rear walls all slopingdownwardly toward each other, said front and side walls being extendedsubstantially in their respective planes to below the bottom of thehopper and forming the front and side walls of a suction box having abottom apex and connected to said hopper at the bottom thereof, and aclosed rear wall for said suction box joined at its upper edge to thelower edge of the hopper rear wall, the rear wall of the suction boxbeing curved concavely toward the front wall thereof and extending tothe apex of the suction box, the maximum spacing between the front andrear walls of the suction box being approximately midway between the topedge of said rear wall and the bottom apex of the suction box.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,320,898 McGuire Nov. fi, 1919 1,322,361 Sherman Nov. 18,1919 1,355,508 Roever Oct. 12, 1920 1,511,018 Fuller Dec. 14, 19261,833,853 Patrono et al Nov. 24, 1931 1,887,768 Maloney Nov. 15, 19322,234,788 Williams Mar. 11, 1941 2,239,010 McMillan Apr. 22, 1941

